1. Field of the Invention
The present invention relates to a keyboard.
2. Description of the Related Art
A flat input keyboard has been known as a keyless keyboard used as an input device for an electronic apparatus such as a personal computer, which enables a key entry operation to be carried out by the function of a touch panel for designating two-dimensional coordinate data, instead of a mechanical key switch using, e.g., a membrane switch (see, e.g., Japanese Unexamined Patent Publication (Kokai) No. 2011-100259 (JP2011-100259A). A touch panel is a panel-type input device (or a coordinate detection device) that can designate two-dimensional coordinate data corresponding to a desired point on a panel surface, to which an operator presses or contacts a pen or a finger.
Generally, irrespective of the types of detecting coordinate data, such as a resistive type, capacitive type, etc., a touch panel has a flat outer surface of an outermost plate-like member (a glass plate, a plastic plate, or a plastic film, etc.) of a panel structure, which serves as an input operation surface adapted to be operated by a pen or a finger. Since the input operation surface is the outer surface of a plate-like member and a touch panel generally has no flexibility in its entirety, a relatively stiff feeling is given on, e.g., the finger from the input operation surface at the time of an input operation. For example, Japanese Unexamined Patent Publication (Kokai) No. 2010-061425 (JP2010-061425A) describes a capacitive-type touch panel provided with an outermost layer having elasticity and made of, e.g., silicone resin, in which, when a user presses the touch panel, the elastic outermost layer is deformed and dented, so as to improve an operational feeling.